Print-chip

Figure 4.28 Relationship of pin load, delivery, and spot diameter. (From Table 1, ChipMaker Micro Spotting Pin Matrix, http //arrayit.com/Products/Printing/Chip-maker/chipmaker.html)...

Electrochemical Genosensor Assay for the Detection of Bacteria on Screen-Printed Chips... 

Numerous electrochemical platforms have been developed for DNA detection, including direct electrochemistry of the DNA bases [5], electrochemistry of different polymer-modified screen-printed chips [6], electrochemistry of DNA-specific redox indicator molecules or enzymes [7,8], electrochemistry of signal amplification with nanoparticles (NPs) such as gold, silver or magnetic particles [9,10], and dsDNA r-stacked mediated charge transport chemistry [4, 7,11,12]. 

In this approach double-stranded oligonucleotide PCR amplicons are labeled with a hapten on one end and another different hapten on the other end during PC R. The transducer surface (gold or carbon screen-printed chips) is treated with protein based anti-haptens that capture one of the hapten label on the PCR amplicons. The second hapten label on the PCR amplicons will bind to a specific anti-hapten-conjugated HRP or AP reporter enzyme to labeled PCR amplicons. Addition of the enzyme-specific redox substrate and application of a fixed potential between working and reference... 

Flexibility of printing (chip layout, medium property independence, adjustability of spot size)... 

Figure 6.7 Screen printed chips with gold (a) electrode structures. The black spots (d) represent the signals observed on chips after enzyme induced silver deposition. SEM images show the ultrastructure of gold (b,c) electrodes. Reproduced from Ref [93] with permission from Elsevier...

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